An end block for a magnetron configuration having a rotating target and a vacuum processing facility having a magnetron configuration of this type are described hereafter, which are constructed simply and are maintenance-friendly.
So-called rotating magnetrons are known in vacuum coating technology, in which a typically tubular target encloses a magnet configuration, the tubular target being mounted so it is rotatable and being drivable so that the target material is ablated uniformly. The tubular target is typically fastened in the vacuum chamber of a vacuum processing facility between two end blocks, which are constructed so that they each allow the rotatable mounting of the tubular target. Different functions are typically assigned to the two end blocks for this purpose. One of the end blocks is typically implemented as a supply end block for supplying a magnetron with cooling water and electrical power and the other end block is implemented as a drive end block for introducing a torque for generating the rotation of the tubular target. End blocks of this type are known, for example, from DE 10 2007 049 735 A1 and WO 2007/147757 A1.
Known end blocks, both supply end blocks and also drive end blocks, are typically connected fixedly to a support apparatus, such as the chamber wall or the chamber cover of a vacuum processing facility, either directly or via a spacer part, which is used for influencing the spacing between magnetron and substrate and is additionally used for the electrical insulation of the end block from the chamber wall or the chamber cover and can be manufactured from an insulating material in this case.
In particular in AC sputtering, heating of the end blocks may arise due to induction eddy currents occurring in the housing of the end block. This heating results in the loss of energy which can no longer be provided to the vacuum process. Furthermore, thermal expansions caused by the heating have unfavorable effects on the magnetron configuration. Moreover, excessively strong heating of the end block can result in damage or even destruction of heat-sensitive components of the end block, such as seals, and thus in the breakdown of the magnetron or the entire vacuum processing facility.
In known end blocks, the heating of the end block occurring in operation is counteracted in that the occurring heat is dissipated by a cooling system integrated in the end block and/or the energy supply is kept low by power limiting. In the first case, an additional cooling apparatus must be provided, which generates additional costs and further increases the energy consumption for operating the vacuum processing facility. In the latter case, in contrast, the performance capability of the magnetron is artificially restricted, whereby the productivity of the vacuum processing facility sinks.
Therefore, an improved end block is to be disclosed, in which the heating by induction eddy currents, which may occur during AC sputtering, for example, is significantly reduced relative to known end blocks.